1. Field of the Invention
The present invention is directed to methods of enhancing food products. Specifically, the present invention is directed to methods of enhancing the puffing characteristics of microwaveable food products such as potatoes, mung beans, wheat, corn, soy beans, rice and rice powders, tapioca, bean starches and starches from other food products and food products obtained therefrom.
2. Background of the Invention
The market for microwaveable snacks focuses on popcorn which the consumer can easily prepare by xe2x80x9cpoppingxe2x80x9d a bag of popcorn immersed in butter flavored oil and salt in the microwave for 2 to 4 minutes. The basis for popping is the retention of moisture in the corn, which xe2x80x9cexplodesxe2x80x9d in the microwave with a popping sound and thereby xe2x80x9cgelatinizesxe2x80x9d the carbohydrates in an expanded state.
There are many known processes for preparing microwaveable snack products. For example, U.S. Pat. No. 5,108,772 issued to Wilbur (hereinafter referred to as xe2x80x9cthe ""772 patentxe2x80x9d) discloses microwaveable poppable pellets and their methods of preparation. Normally, the consumer can tell when the product is finished in the microwave oven when the sound of popping ceases. A problem with using puffable pellets in place of popcorn in a microwave snack is the lack of a sound cue to indicate completion of the microwave-heating step because the pellets expand gradually rather than explode as does popcorn. However, Thus, a consumer would have to rely on visual cues to determine the completion of the microwave-heating step. The ""772 patent solves this problem by providing a pellet having an outer skin or casing of sufficient tensile strength to allow the buildup of internally generated steam pressure. When the pressure is sufficient, the pellet explodes explosively thus giving an audible clue of the termination of the microwave heating step. Thus, the microwave snacks prepared according to the ""772 patent resemble that of popcorn kernels. However, the food products prepared from this process are complicated to make and does not have the same desirable characteristics of a normal puffable product.
U.S. Pat. No. 6,083,552, issued to Kershman, et al. (hereinafter referred to as xe2x80x9cthe ""552 patentxe2x80x9d) discloses microwaveable snacks composed of a combination of popcorn and expandable or puffable food pellets. The combination of these two products minimizes scorching and burning of the starched-based puffable component of the mixture.
Food products from known processes such as those pellets disclosed in the above patents have solved the problem of providing a solely starch-based product which exhibits puffing uniformly without combining popcorn.
Also, in general, microwaveable food products are believed to have better puffabilty when their shapes are round because the corner parts in square shapes tend to remain uncooked. The ""772 patent limits the disclosed pellets to a rounded shape
Generally, the shapes disclosed in these patents are produced by extrusion, press molding and the like. However, if the shaped product is produced by dye cutting, i.e., by forming a sheet of the product and cutting out the shape with a die, e.g., in cookie cutter fashion, problems can arise due to material loss. Thus, the material between the die cuts is non usable.
We have discovered a method for preparing a food product which can be quickly cooked by rapid cooking processes, such as microwaving, hot air heating, e.g., by passing heated air at a temperature of about 400-480 C.xc2x0 over the food product, or deep fat frying in oil that has been preheated to a temperature of at least 340 to 345xc2x0 C. The inventive product exhibits excellent puffable characteristics. As used herein, the term xe2x80x9cpuffablexe2x80x9d means the ability of the product or pieces thereof to expand in volume, usually at least by twofold, within a short time, e.g., from several seconds to less than two minutes, when subjected to rapid heating. The term xe2x80x9cpiecexe2x80x9d herein means a discrete shape element of the food product, usually capable of being contained in a bag for selling to the consumer. The inventive food product is easily cooked by such rapid heating to obtain a delicious crunchy snack without problems, such as, overcooking or the need to utilize components to provide audible cues as to cooking times, e.g., popcorn kernels.
The inventive food product is obtained by first mixing a gelatinizable starch containing only trace amounts of protein with water at a temperature and for a time sufficient to at least partially gelatinize the starch. The thus treated mixture is then formed into a sheet and subjected to a steam treatment to completely gelatanize the starch. The sheet is then shaped into pellets by die cutting and the pellets are dried to a moisture contend of about 7.5 to 19.0 percent by weight. All percent weights used herein are based on the weight of the total composition
The inventive mixture has a moisture content in the range of from about 7.5% to about 19.0% by weight. All weights expressed herein are percentage weight based of the total mixture. Preferably, the moisture content of the mixture is from about 8% to about 16% by weight of the mixture. Even further preferably, the moisture content of the mixture is from about 10% to about 15% by weight of the mixture. Most preferably, the moisture content of the mixture is from about 11% to about 14% by weight of the mixture. In yet another preferred embodiment, the moisture content of the mixture is about 12% by weight of the mixture.
Starch suitable for use in the present invention include starch obtained from potatoes, mung beans, wheat, corn, soy beans, rice and rice powders, tapioca, beans. Mixtures of such starches may be used Preferably, the food product is formed from 100% potato starch. The starch from each of the above named sources each possesses somewhat different characteristics, although all are usable in the inventive method. However, the most preferred starch source is potato starch. Depending on the end product desired, potato starch may be mixed with small amounts of starch from any one or more of the other named starch sources. For example, the different starches provide different textures, and may vary in puffability characteristic somewhat and the skilled worker in this field would have no problem varying the composition to achieve her desired end characteristics.
It is contemplated that several different seasonings can be used in the method of the present invention. Preferably, the seasoning is selected from the group including salt, vinegar, barbecue seasoning, nacho seasoning, sour cream and onion seasoning, sweet and sour seasoning, sweet seasoning, hot and spicy seasoning, chicken flavor seasoning, savory flavor seasoning, fruit seasonings, citrus seasoning, vegetable seasonings, MSG, HVP, Yeast Autolysates flavor reaction products and other natural and artificial flavored seasonings such as fruit, vegetable and dairy flavored seasonings.
The food products or pellets prepared by the method of the present invention can include virtually any shape obtainable by die cutting of a sheet, e.g., round, square, triangular, and the like. The inventive food products prepared by the method of the present invention may be cooked by any type of rapid heating procedure. Typically, these include microwaving, hot air, e.g., heating in a hot air device, such as, those use for hot air popping of popcorn, deep fat frying. These are all methods which heat the food product to a high temperature at a relatively high speed, e.g., in a matter of seconds or in less than a minute or two. The inventive food products can also be cooked using other xe2x80x9cexplosionxe2x80x9d processes such as those used in cereal manufacturing, or the like. Regardless of what process is used to cook the food products, the inventive food product still exhibits excellent and puffing characteristics. Further, the expanded food products have very good texture, mouth feel and taste characteristics.
The mixture of the starch and water may be heated in a variety of methods to effect at least partial gelatinization of the starch. Typically, a jacket mixer may be used. While the heating temperature used for this step is dependant on the type of starch, i.e., the starch source, generally, the mixture is heated at a temperature of from about 55.0xc2x0 C. to 70.0xc2x0 C. For potato starch, the mixture of starch and water is heated at a temperature of from about 60.0xc2x0 C. to 65.0xc2x0 C. for a time period of from about four to six minutes to effect at least partial gelatinization. It is best that the starch not be completely gelatinized in this step since the mixture increases in viscosity with increased gelatinization and it must be sufficiently pourable to form into sheet form. To some extent the amount of gelatinization depends on the properties of the particular starch, i.e., the source of the starch.
The partially gelatinized mixture is then formed onto a sheet. This is generally accomplished by pouring the mixture into a flat pan or onto a conveyor or roller belt for continuous processing. The thickness of the sheet is generally is in the range from about 0.9 mm to 3.0 mm prior to the steam treatment. Preferably the sheet thickness prior to the steam treatment is from about 1.3 mm to 2.7 mm and most preferably from about 1.3 mm to 1.7 mm. The thickness of the sheet prior to the steam treatment is not particularly critical, but does effect the thickness of the final product since the die cut pellets are dried after the cutting. Thus, the thickness of the dried pellets corresponding to the above presteaming thickness, respectively, would be about 0.4 mm to 2.7 mm, preferably from about 0.8 mm to 2.4 mm and most preferably about 0.8 mm to 1.4 mm.
After the mixture is formed into a sheet and the sheet is subjected to a steam treatment. This effects complete gelatinization of the mixture. The steam treatment is carried out by contacting the sheet with steam for a period of time to produce complete gelatinization. This can be achieved by placing the sheet into a steam oven or other procedures well known in the art. The steam treatment may be carried out under atmospheric pressure. The amount of time required for the steam treatment depends on the thickness of the sheet and source of the starch. Generally, the steam treatment is carried out for about 1 to 7 minutes at a steaming temperature of about 95 to 100xc2x0 C. longer steaming may occasionally result in producing a unevenness in the surface of the sheet, e.g., craters may form in the surface. Preferably, the steaming time is about 1 to 5 minutes for a continuous or in-line process and about 3 to 6 minutes for a batch steamer. The most preferred time required for steaming is from about 3 to 5 minutes.
After the steam treatment, the sheet is cooled and allowed to dry. This can be effected by air drying or heating. It is important that the sheet be dried only to the extent such that it can be cut or formed into the desired pellet shape. Thus, if the sheet is dried too much, it may become too brittle so that when it is shaped, as by die cutting, the pellets will fracture. The degree of dryness is easily adjusted by the skilled artisan to achieve the desired result, i.e., size and shape of the pellets. Usually, the finish product in pellet form have a moisture content of from 7.5 to 19% by weight.
The product of the present invention exhibits excellent puffing characteristics when rapidly heated, e.g., in a microwave oven, hot air popper or when subjected to deep fat frying. In addition, depending on the starch source and the amount and type of seasoning added in accordance with the invention, one may obtain an audible popping or cracking sound when the pellets are being heated so that an audible signal is provided to determine when the heat time is finished. Also, if the pellets are packaged in a microwave cooking bag, upon heating of the bagged product, the bag expands and the consumer can determine when the cooking is done by visual observation of the cessation of the expansion of the bag.
As used herein, the phrase xe2x80x9cshapingxe2x80x9d includes the steps of cooling the sheet after die cutting and drying it as well as any other conventional steps required to form expandable compositions hereinafter referred to as xe2x80x9cpellets.xe2x80x9d
The following examples are provided to assist in further understanding the present invention. The particular materials and conditions employed are intended to be further illustrative of the invention and are not limiting upon the reasonable scope thereof.